Roduktivitas Alat Gali Muat PC 1250 dalam Operasi Overburden Menggunakan Metode Simpleks pada Pit Paradise PT Pamapersada Nusantara Site Asmin Bara Bronang

Abstract

This study aims to analyze the factors affecting productivity and to optimize the performance of the Komatsu PC1250-11R excavator in overburden stripping activities at Pit Paradise, PT Pamapersada Nusantara, Asmin Bara Bronang Site, Central Kalimantan. Before optimization, the actual productivity of the excavator was 377.06 bcm/day, equivalent to 63% of the production target of 600 bcm/day. A quantitative approach was applied using primary data obtained from direct field observations, including excavator cycle time, bucket fill factor (BFF), work efficiency (EFF), material conditions, loading point geometry, and loading patterns. Secondary data were collected from company documents, including overburden production reports, equipment specifications, hauling unit data, working hours, and operational standards. The results show that low productivity prior to optimization was mainly influenced by non-blasting and hard material conditions, loading point geometry that did not meet operational standards (average bench height of 1.9 m and front width of 18.2 m), and the use of inefficient top loading/double bench patterns. The average BFF of 79% and EFF of 93% indicate that the excavator performance still had potential for improvement. Optimization was performed using the Simplex method as a linear programming technique to determine the optimal combination of decision variables. The decision variables consisted of excavator working time under single back loading (x₁) and top loading (x₂) patterns. After optimization, all working time was allocated to the single back loading pattern, resulting in an increase in productivity from 11,689.86 bcm/month to 20,646.64 bcm/month, equivalent to 666.02 bcm/day, with an efficiency level of 100%. Furthermore, the Match Factor (MF) increased from 0.56 before optimization to 0.85 after optimization, indicating an improved balance between excavating and hauling equipment.